From 48df05b16dba362366b63284c2e551c51995fb66 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Wojciech=20K=C4=99pka?= <wojtek.kepka@protonmail.com>
Date: Tue, 8 Jun 2021 08:25:55 +0200
Subject: [PATCH] commands: Add goto first non-whitespace char of line

---
 book/src/keymap.md         |  1 +
 helix-core/src/lib.rs      | 12 ++---------
 helix-term/src/commands.rs | 41 +++++++++++++++++++++++++++++++++++++-
 3 files changed, 43 insertions(+), 11 deletions(-)

diff --git a/book/src/keymap.md b/book/src/keymap.md
index 705c4ab1..c7ffbb26 100644
--- a/book/src/keymap.md
+++ b/book/src/keymap.md
@@ -133,6 +133,7 @@ Jumps to various locations.
 | e   | Go to the end of the file |
 | h   | Go to the start of the line |
 | l   | Go to the end of the line |
+| s   | Go to first non-whitespace character of the line |
 | t   | Go to the top of the screen |
 | m   | Go to the middle of the screen |
 | b   | Go to the bottom of the screen |
diff --git a/helix-core/src/lib.rs b/helix-core/src/lib.rs
index cfe466ed..da48ba7e 100644
--- a/helix-core/src/lib.rs
+++ b/helix-core/src/lib.rs
@@ -18,16 +18,8 @@ pub mod syntax;
 mod transaction;
 pub mod words;
 
-pub(crate) fn find_first_non_whitespace_char2(line: RopeSlice) -> Option<usize> {
-    // find first non-whitespace char
-    for (start, ch) in line.chars().enumerate() {
-        // TODO: could use memchr with chunks?
-        if ch != ' ' && ch != '\t' && ch != '\n' {
-            return Some(start);
-        }
-    }
-
-    None
+pub fn find_first_non_whitespace_char2(line: RopeSlice) -> Option<usize> {
+    line.chars().position(|ch| !ch.is_whitespace())
 }
 pub(crate) fn find_first_non_whitespace_char(text: RopeSlice, line_num: usize) -> Option<usize> {
     let line = text.line(line_num);
diff --git a/helix-term/src/commands.rs b/helix-term/src/commands.rs
index 2412e55d..fc1b363c 100644
--- a/helix-term/src/commands.rs
+++ b/helix-term/src/commands.rs
@@ -1,5 +1,6 @@
 use helix_core::{
-    comment, coords_at_pos, find_root, graphemes, indent, match_brackets,
+    comment, coords_at_pos, find_first_non_whitespace_char2, find_root, graphemes, indent,
+    match_brackets,
     movement::{self, Direction},
     object, pos_at_coords,
     regex::{self, Regex},
@@ -216,6 +217,24 @@ pub fn move_line_start(cx: &mut Context) {
     doc.set_selection(view.id, selection);
 }
 
+pub fn move_first_nonwhitespace(cx: &mut Context) {
+    let (view, doc) = cx.current();
+
+    let selection = doc.selection(view.id).transform(|range| {
+        let text = doc.text();
+        let line_idx = text.char_to_line(range.head);
+
+        if let Some(pos) = find_first_non_whitespace_char2(text.line(line_idx)) {
+            let pos = pos + text.line_to_char(line_idx);
+            Range::new(pos, pos)
+        } else {
+            range
+        }
+    });
+
+    doc.set_selection(view.id, selection);
+}
+
 // TODO: move vs extend could take an extra type Extend/Move that would
 // Range::new(if Move { pos } if Extend { range.anchor }, pos)
 // since these all really do the same thing
@@ -421,6 +440,24 @@ pub fn extend_prev_char(cx: &mut Context) {
     )
 }
 
+pub fn extend_first_nonwhitespace(cx: &mut Context) {
+    let (view, doc) = cx.current();
+
+    let selection = doc.selection(view.id).transform(|range| {
+        let text = doc.text();
+        let line_idx = text.char_to_line(range.head);
+
+        if let Some(pos) = find_first_non_whitespace_char2(text.line(line_idx)) {
+            let pos = pos + text.line_to_char(line_idx);
+            Range::new(range.anchor, pos)
+        } else {
+            range
+        }
+    });
+
+    doc.set_selection(view.id, selection);
+}
+
 pub fn replace(cx: &mut Context) {
     // need to wait for next key
     cx.on_next_key(move |cx, event| {
@@ -1288,6 +1325,8 @@ pub fn goto_mode(cx: &mut Context) {
                 (_, 'y') => goto_type_definition(cx),
                 (_, 'r') => goto_reference(cx),
                 (_, 'i') => goto_implementation(cx),
+                (Mode::Normal, 's') => move_first_nonwhitespace(cx),
+                (Mode::Select, 's') => extend_first_nonwhitespace(cx),
 
                 (_, 't') | (_, 'm') | (_, 'b') => {
                     let (view, doc) = cx.current();